from threading import Timer
import time

def timeout():
    print "Game over"

t = Timer(20 * 60, timeout)
t.start()

from threading import Timer
import time
class RenewableTimer():
    def __init__(self, timeout, callback):
        self.timeout = timeout
        self.callback = callback
        self.timer = Timer(timeout, callback)
    def cancel(self):
        self.timer.cancel()
    def start(self):
        self.start_time = time.time()
        self.timer.start()
    def pause(self):
        self.cancel_time = time.time()
        self.timer.cancel()
        return self.get_actual_time()
    def resume(self):
        self.timeout = self.get_actual_time()
        self.timer = Timer(self.timeout, self.callback)
        self.start_time = time.time()
        self.timer.start()
        return self.timeout
    def get_actual_time (self):
        return self.timeout - (self.cancel_time - self.start_time)